Firearm



J. DESTREE FIREARM Filed April 5, 1930 DES WEE.

'ATTY.

Patented Earn. 3, 1931 UNITED STATES PATENT OFFICE JOSEPH DESTREE, OF BRUSSELS, BELGIUM Application filed April 5, 1980, Serial No. 442,008, and in Belgium April 18, 1929.

The present invention relates to a firearm in which the breech recoils under the action of the pressure of the gases and in particular to a firearm in which this movement of recoil l) of the breech already takes place during the whole of the time that the projectile is still in the barrel.

The object of the invention is to soften the recoil movementof the breech.

For this purpose, the invention provides for this movement of recoil to be damped by the gases taken from the barrel at a distance from the breech at least equal to a number of times the length of the cartridge.

The invention provides in particular for these shock absorbing gases to act on a member connected mechanically to the breech, the said gases tending to displace this member in the reverse direction to the recoil of the breech.

Other details and features of the invention will appear from the course of the description of the accompanying drawings which illustrate diagrammatically in perspective two forms of construction of the invention.

Figure 1 is an axial section with parts cut away of the barrel and of the breech of a firearm with internal recoil provided with a breech damping device according to the invention.

Figure 2 is an axial section of a modified form of the invention.

Referring more particularly to Figure 1, this figure shows the barrel 2 of a firearm the interior of which communicates through a duct 3 with the cylinder 4. This duct 3 is situated at a distance from the breech at least equal to a number of times the length of the cartridge 8.

In the case shown this duct is even situated near the back part of the barrel.

This cartridge comprises a cylindrical case to prevent it from deforming and bursting during the time it recoils under the pressure of the gases which are still in the barrel.

The gases admitted into the cylinder 4 through the duct 3 act on a piston 5 connected by a rod 562 to the breech, 6.

In the case shown, the latter is never locked. Its movement of recoil under the action of the gases which expel the projectile,

by being damped by the action of the gases acting on the piston 5 is particularly gentle. Consequently the mass of the breech which is fairly great when the damping action ac'cordin to the invention is not applied, may be re need to a considerable extent.

In order to permit the suitable recoil of the breech 6, the invention provides for the braking action of the gases acting on the piston 5 to be reduced. This reduction may be obtained by reducing the pressure of these gases for example by drawing oif the shock absorbing gases from near the outlet end of the barrel.

This reduction in pressure may also be effected by providing holes such as 4a in the cylindrical wall 4.

Instead of connecting the breech 6 to a piston moving under the action of the gases in a cylinder, it may also be connected by a rod 5a as shown in Figure 2, to a sleeve 7 arranged at the outlet end of the barrel 2. This sleeve 7 has an aperture larger than the internal diameter of the barrel 2. Its form is such that the jet of gas issuing from the barrel will have a tendency to carry it in the reverse direction of movement to that of the recoil of the breech.

Whatever be the arrangement adopted, the shock absorbing gases cease to act at the same time as those which produce the recoil of the breech, because they are in free communication with the interior of the barrel.

It is obvious that the invention is not exclusively limited to the form of construction shown and that many modifications may be made in the shape and in the arrangement of the members employed in its construction without going outside the scope of the present invention. a

It is further obvious that the braking device according to the invention may be applied to other breech blocks than those which are never looked, provided that these breech blocks recoil under the action of the pressure of the gases in the barrel. These breech blocks may for example recoil after a releaslng action itself efiected bv the action of the gases. V

What I claim is:

1. An automatic firearm comprising a breech which recoils under the pressure of the gases in the barrel, a movable member, means for connecting positively this movable member with the breech and means for leading the gases in the barrel from a point of the lat" ter at a distance from the breech equal to a number of times the length of the cartridge case onto the face of this movable member to damp the recoil of the breech directly by the gases.

2. An automatic firearm comprising a breech which recoils under the pressure of the gases in the'barrel, a movable member, means for connecting positively this movable member with the breech, and means for leading the gases in the barrel from a point near the outlet of the latter onto the face of this movable member to damp the recoil of the breech directly by the gases.

3. An automatic firearm comprising a breech which recoils under the pressure of the gases in the barrel, a movable member disposed near the outlet of the barrel, means for connecting rigidly this movable mem-' her with the breech, and means for leading the gases in the barrel from a point near the outlet of the latter onto the face of this movable member to displace the latter towards the outlet of the barrel.

In testimony whereof I aflix my signature.

JOSEPH DESTREE. 

